Featured Research

from universities, journals, and other organizations

Brief Exposure To High Temperatures Has Lasting Effect On Nervous System

Date:
February 23, 1999
Source:
University Of Chicago Hospitals & Health System
Summary:
Researchers at the University of Chicago in collaboration with scientists at Queens University in Ontario, Canada, have shown for the first time that brief exposure to high temperatures has long-lasting physiological effects on the nervous system. These changes, which the researchers measured in locusts, may be what enables the animals to fly in very hot environments.

Researchers at the University of Chicago in collaboration with scientists at Queens University in Ontario, Canada, have shown for the first time that brief exposure to high temperatures has long-lasting physiological effects on the nervous system. These changes, which the researchers measured in locusts, may be what enables the animals to fly in very hot environments.

The study, published in the February issue of the Journal of Neurophysiology, is also the first to use a new technique, allowing scientists to measure changes in neuronal activity in insects' minute brains.

"Scientists have suspected that heat shock has adaptive properties for all kinds of animals, we just haven't had any direct evidence until now," says Nino Ramirez, Ph.D., assistant professor of organismal biology & anatomy at the University of Chicago. Ramirez and R.M. Robertson, Ph.D., professor of biology at Queens University, decided to look into how heat exposure effects the locust's ability to fly.

"Locusts that are transferred from cooler places to a warm desert have trouble flying and some even die," says Ramirez. "But locusts exposed to brief periods of high temperatures and later released into the desert can fly normally. We thought that previous heat exposure might have changed the properties of the neurons somehow," says Ramirez.

To test the idea that heat shock induces lasting modifications of neuronal properties, Ramirez and Robertson exposed 50 locusts to 45 degree Celsius temperatures (about 112 degrees Fahrenheit) for 3 hours, while control locusts were kept at room temperature (about 70 degrees Fahrenheit) for the same amount of time. Heat-shocked locusts were allowed 6 to 24 hours to recover.

"We couldn't measure activity in single neurons because they are too tiny," Ramirez says. "We had no choice but to measure from slices of the brain which are large enough to preserve relatively intact neuronal activity, but thin enough for us to insert measuring devices. To do this, we had to create a whole new procedure for taking slices of the insect's brain, something that no one had done before," says Ramirez.

Cells in the slices were kept alive in a petri dish and Ramirez monitored the neurons using tools thinner than a human hair. What the researchers found surprised them. "We expected to see some changes in the flow of calcium from the neurons, but instead, we found that potassium outflow from the neurons of heat-shocked locusts was greatly reduced," says Ramirez.

The significance of this difference is not yet known, but Ramirez suspects that it might reduce the sensitivity of the locust's flight motor neurons, allowing the insect to fly in ultra-high temperatures. "There is definitely adaptive significance to the change in potassium levels, although more investigation is required to determine exactly how the changes influence the locust's ability to fly in extreme heat," Ramirez explains.

Next, Ramirez wants to see if heat shock has the same neuroprotective role in invertebrates. "If we see the same effect in mice we can start trying to figure out exactly how heat shock plays this protective role," says Ramirez. "Then we might be able to mimic those protective effects in cases where the nerves are undergoing trauma, like in stroke patients where the nerves are starved and attacked by free radicals."


Story Source:

The above story is based on materials provided by University Of Chicago Hospitals & Health System. Note: Materials may be edited for content and length.


Cite This Page:

University Of Chicago Hospitals & Health System. "Brief Exposure To High Temperatures Has Lasting Effect On Nervous System." ScienceDaily. ScienceDaily, 23 February 1999. <www.sciencedaily.com/releases/1999/02/990223082305.htm>.
University Of Chicago Hospitals & Health System. (1999, February 23). Brief Exposure To High Temperatures Has Lasting Effect On Nervous System. ScienceDaily. Retrieved July 25, 2014 from www.sciencedaily.com/releases/1999/02/990223082305.htm
University Of Chicago Hospitals & Health System. "Brief Exposure To High Temperatures Has Lasting Effect On Nervous System." ScienceDaily. www.sciencedaily.com/releases/1999/02/990223082305.htm (accessed July 25, 2014).

Share This




More Health & Medicine News

Friday, July 25, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Beatings and Addiction: Pakistan Drug 'clinic' Tortures Patients

Beatings and Addiction: Pakistan Drug 'clinic' Tortures Patients

AFP (July 24, 2014) A so-called drugs rehab 'clinic' is closed down in Pakistan after police find scores of ‘patients’ chained up alleging serial abuse. Duration 03:05 Video provided by AFP
Powered by NewsLook.com
Too Few Teens Receiving HPV Vaccination, CDC Says

Too Few Teens Receiving HPV Vaccination, CDC Says

Newsy (July 24, 2014) The Centers for Disease Control and Prevention is blaming doctors for the low number of children being vaccinated for HPV. Video provided by Newsy
Powered by NewsLook.com
New Painkiller Designed To Discourage Abuse: Will It Work?

New Painkiller Designed To Discourage Abuse: Will It Work?

Newsy (July 24, 2014) The FDA approved Targiniq ER on Wednesday, a painkiller designed to keep users from abusing it. Like any new medication, however, it has doubters. Video provided by Newsy
Powered by NewsLook.com
Doctor At Forefront Of Fighting Ebola Outbreak Gets Ebola

Doctor At Forefront Of Fighting Ebola Outbreak Gets Ebola

Newsy (July 24, 2014) Sheik Umar Khan has treated many of the people infected in the Ebola outbreak, and now he's become one of them. Video provided by Newsy
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:
from the past week

In Other News

... from NewsDaily.com

Science News

    Health News

      Environment News

        Technology News



          Save/Print:
          Share:

          Free Subscriptions


          Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

          Get Social & Mobile


          Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

          Have Feedback?


          Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
          Mobile: iPhone Android Web
          Follow: Facebook Twitter Google+
          Subscribe: RSS Feeds Email Newsletters
          Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins